Lubricating oil



Patented June 15, 1943 tnnnroarrno on Lloyd L. Davis, Bert ll. Lincoln, and Gordon D.

Byrlrit, Ponca City, Okla, assignors to Continental Oil Company, Ponca City, Okla, a corporation of Delaware No Drawing.

8 Claims.

filed April 18, 1940 now Patent No. 2,236,897.

Two general methods of obtaining high viscos ty index oils have been described in the literature of the art, namely, the production ofv synthetic or synthetically treated oils with high viscosity index and the addition of various materials to ordinary or low viscosity index oils to improve them. Our products are of the first type and are intended to be used directly as lubricating oils.

Application September 5, 1940, Serial No. 355,462

eating oils having extremely high viscosity indices. Another object of our invention is to utilize non-lubricant petroleum fractions to produce improved lubricating oils.

A further object of our invention is to synthesize materials which may be used to improve the characteristics of ordinary lubricating oils.

A still further object of our invention is to convert materialsoi low economic value into valuable products by a commercially feasible process.

. Other objects of our invention will appear from the following description.

Briefly our invention consists in the production of mixed cyclic and alkyl ethers of the type RXR' In the prior art of synthesizing oils of lubriin which R is a high molecular weight aliphatic eating properties, various processes have been radical containing carbon, hydrogen, and at employed as well as various starting materials. least one other characterizing element selected For example, lubricating oils have been prepared from the group consisting of oxygen, sulfur, nitroby the action of polymerizing reagents such as gen, or phosphorus. R is an organic radical conaluminum chloride, ferric chloride, phosphoric 2; taining a carbocyclic or heterocyclic nucleus acid and phosphates, boron fluoridefand the like which ma or may not bear various alkyl or other on lower oiefins such as ethylene, propylene, substituting groups. It is necessary to have at butylenes, and higher olefins such as hexene, least 13 carbon atoms in the aliphatic radical in octene, and even cetene, ClGHIrZ. Various mixed order to obtain as products lubricating oil havolefins have been polymerized such as cracked ing viscosities of at least seconds Saybolt at gases, cracked paraffin wax and the like. 100 F. In the above formula, X stands for an Synthetic lubricating oils have been prepared atom of an element of the right-hand side of by various condensation reactions. For example, group VI of the periodic table, that is, oxygen, the condensation of halogenated wax or other pesulfur, selenium, or tellurium. f troleum fractions with aromatic hydrocarbons or Whileordinary lubricating oils have viscosity other aromatic compounds such as naphthalene, indices from as low as 40 for naphthenic oils diphenyl ether and the like. y l to or for Pennsylvania oils, the products The products of our invention are more cheaply of our invention have viscosity indices of not less and easily made than other synthetic lubricating I than 90. oils. They have higher viscosity indices than any .15 It is to be understood that the hydrocarbon previously reported. Furthermore, we utilize radicals may be modified so as to bear another non-lubricating fractions of petroleum to procharacterizing element in addition to carbon and on e these high quality lubricating oils. Our hydrogen before our product is finished. These products are, like the so-called white oils, excharacterizing elements are oxygen, sulfur, nitremely stable toward oxidation and sludging 40 trogen, and phosphorus and may be present in which is not true of ordinary lubricating oils. R, or R of the above formula or in both radicals By our processes, we convert materials of low in the form of any of their-particular groupings economic value into products of greatly enhanced with other elements. Some of the groups convalue. taining these elements which may be present in One object of our invention is t provide lubri- 4 R or R, or both are:

onour 4002s I -NECO2R -o.co.a -s con, s as a NH.COR

in which R is a hydrocarbon or substituted hydrocarbon radical.

The aliphatic radicals of our products may be derived from any source and may be of various degrees of purity, that is, freedom from other types of radicals. For example, cetyl chloride is a suitable source of the cetyl radical. We may utilize paraflin hydrocarbons of various petroleum fractions as sources of aliphatic radicals including hydrocarbons of the heavy ends of ordinary gasoline, kerosene, gas oil, paraflin wax and higher paraflin hydrocarbons from natural or synthetic sources. One preferred source of aliphatic radicals of the type described is a relatively pure monochlor parafiin wax, dichlor parafiln wax or the like.

In the prior art, references are made to monochloro paraflln, dlchloro paraflin, trichloro paraflin, and the like. It is usually considered that the product of direct chlorination is the compound represented by the total chlorine content and therefore the desired compound. We have found that these products of chlorination are very crude mixtures of the chlorinated hydrocarbons and contain unchlorinated hydrocarbons and the mono-, di-, and polychloro derivatives. The whole mixture cannot be considered the desired compound. For example, a so-called "trichloro paraflln wax" containing 24 per cent chlorine, which corresponds very closely to the percentage of chlorine in the trichloro compound,

was separated by means of crystallization from acetone at low temperatures. The least soluble portion consisted of unchlorinated wax. The next least soluble portion consisted of a mixture of monochloro wax and unchlorinated wax. The percentage of unchlorinated wax in the original mixture, supposedly "trichloro paraflln wax, was found to be 7.2 per cent. Thus, even a trichloro paraflln" as so-called in the prior art, because of the total chlorine content, was in fact a crude mixture containing as much as 7.2 per cent of unchlorinated wax and quantities of monoand di-chloro waxes, as well as trichloro wax and more highly chlorinated waxes. Its use would not give the same results as a trichloro paramn free of higher and lower chlorinated parailln, since the products will contain unhalogenated paraflln hydrocarbons and mixed derivatives.

Even though the appropriate amount of chlorine is introduced in the wax to form a monochloro wax, we have found that the crude chlorination mixture contains, in addition to small amounts of chlorine and hydrogen chloride and the desired monochlor wax, also unchlorinated wax and more highly chlorinated waxes. When dichlor and higher chlor wax is the desired product, the crude chlorination mixture will contain in addition to chlorine and hydrogen, less highly chlorinated waxes.

In contrast to the use of such a mixture, we have found it possible, as fully described below. to obtain a relatively pure monochlor compound free from unchlorinated hydrocarbon and free from more highly chlorinated compound. We may thus prepare (1) monohalogenated hydrocarbons substantially free from unhalogenated hydrocarbons and more highly halogenated hydrocarbons; (2) dihalogenated hydrocarbons substantially free from unhalogenated hydrocarbons and monolialogenated hydrocarbons, as well as from halogenated hydrocarbons containing more than two atoms of halogen per molecule; and (3) trihalogenated hydrocarbons free from halogenated hydrocarbons containing fewer or more than three halogen atoms per molecule and free from unhalogenated hydrocarbons. We refer in this specification to these materials as relatively pure monohalogen compounds, relatively pure dfhalogen compounds, etc.

The chlorination of most petroleum hydrocarbons lowers their melting points and, up to a certain point, the greater the extent of chlorination; that is', the more chlorine atoms per molecule, the lower the melting point. The decrease in melting point is stepwise, and this permits us to separate the unchlorinated hydrocarbons from the monochloro hydrocarbons and the monochloro hydrocarbons from the dichloro and higher chlorinated hydrocarbons. We can, for example, separate the unchlorinated wax from the airblown mixture by filter pressing at such temperatures that all of the chlorinated waxes are largely liquids, while the unchlorinated waxes are largely solid. The temperature for the pressing operation will depend, of course, on the character of the wax used initially and will vary considerably depending on this factor. For example, at a temperature of from F. to F. the monochloro product formed by the chlorination of wax having a melting point of P. will be liquid, while the unchlorinated wax will be solid, enabling a ready separation to be effected.

Other methods of separation, as for example, sweating, selective solvent extraction at various temperatures, the use of diluents followed by chilling and settling or filtering, and the like, may be employed for separating solid unchlorinated wax from chlorinated portions, and for separating the monochloro wax from the more highly chlorinated portions, and so on. In separating relatively pure monochlor, dichlor, etc., hydrocarbons from such sources as the heavy ends of gasoline, kerosene and the like, we preferably use chilling only as a method of separation since in solution extremely low temperatures are required. Solvents may be used here, of course, but it is more convenient to depend simply on differences in melting point. It will be obvious to those skilled in the art that in these cases it is not practicable to employ difierences in boiling point since the halogen derivatives of the lower hydrocarbons will have the same boiling range as unhalogenated higher boiling hydrocarbons in the same fraction of starting material.

The unchlorinated wax separated from the crude chlorination mixture may be recycled to the chlorination step to obtain further quantities of chlorinated waxes. It does not represent refractory material, and the same proportions of chlorination products are obtained from it as from fresh wax.

The liquid chlorinated waxes after separation of unchlorinated hydrocarbons consist largely of monochloro and dichloro waxes when approximately 10 or 20 per cent chlorine respectively is introduced into a starting wax, of, say, from 115 to F. melting point, but some polychloro wax may be' present. These monoand dichloro waxes may be separated from each other by crystallization from acetone. using a solventchlor wax ratio of from 1 to 1 to 20 to 1. In preparing the solution, an elevated temperature may be employed to insure that the chloro waxes are completely dissolved in the solvent. The solution is then chilled to a temperature of between minus 15 F. and minus 20 F. when a paramn wax 0! 115 to 130 F. melting point is used for the initial chlorination. The monochloro waves are precipitated out nearly quantitatively, while the dition. The precipitated monochloro waxes may be readily separated by settling, filtering, or centrifuging. a

We have also used other crystallization solvents such as methyl-ethyl ketone, acetone, benzene, methylene chloride, various other halogenated solvents as well as liquid propane or butane. Mixtures of twoor more solvents may be usedrThe use of a particular one or combination ofthese solvents requires the experimental determination of the proper proportions and temperatures necessary to obtain the desired separationof the crude chlorination mixture into the various stages of chlorine contents. Halogenated solvents serve to aid in the precipitation of unchlorinated wax, while benzene and hydrocarbon solvents increase the solubility of the more highly chlorinated materials.

After removing the monochlor wax, the solution may be chilled to a lower temperature or concentrated by distillation or evaporation of the solvent or both to precipitate the dichlor waxes which may then be separated. A further separation of the remaining liquid may be accomplished by repetition ofthese processes. In this manner, the crude chlorination mixture 'may 'be separated into unchlorinated wax, monochlor wax, dichlor waxand polychlor wax. We proved the homogeneity of our monochlor wax, for example, by chil ing until approximately half of the sample had solidified. Solid and liquid portions were separated by filtration and contained 12.1 and 11.4 per cent chlorine respectively. In the case of the wax whichhadthe 120 F. melting point, batches showed chlorine contents of 10.2, 10.3, and 10.5 per cent. These values are very close to the theoretical of 10.0 per cent. Thus,

our relatively pure monochlor wax is substantially free from unchlorinated wax and more highly chlorinated waxes. We may prepare according to our invention similarly pure diand polychlor waxes free from unchlorinated wax and more highly chlorinated waxes.

Our paraflin hydrocarbons are preferably obtained from petroleum, though it is to be understood that any source rich in hydrocarbons of the paraflin series may be used as starting materials in practicing our invention. Our method is particularly applicable to the higher paraflin hydrocarbons such as represented by ordinary paraflin wax, but it is to be understood that it may be practiced .on paraffin hydrocarbons of higherand lower molecular weight including all those paraflin hydrocarbons whose monochloro derivatives chloro and polychloro waxes will remain in solu and pass chlorine gas through the melted hydro- I chlorine absorption but is not essential.

number of chlorine atoms per molecule.

which will produce the dichloro compound when that is the desired product, etc.

In the case of paraiiin hydrocarbons having from 18to 24 carbon atoms per molecule, that is, amaterial having a melting point of approximately 120 F., about 10 per cent added chlorine will producesubstantially the equivalent of the monochlor product. The amount of chlorination may vary between 9 per cent and 12 per cent without being disadvantageous; The percentage .of chlorine introduced into the hydrocarbon just describedwill be approximately 17 per cent when a dichloro product is desired. The amount of bons. and more in the case of the lowermolecular weight, lower melting hydrocarbons, fora given The chlorination may be accomplished in any suitable mannen We prefer to heat the hydrocarbon'to a temperature at least that of its melting point carbon. Agitation increases the efficiency of The chlorination reaction is exothermic and the heat of reaction is ordinarily ample to maintain the mixture in the liquidstate without the addition Large'quantities of hydrogen chloride gas are evolved which are conducted of other heat.

from the reaction chamber. together with unreacted chlorine. material being chlorinated is constantly weighed while the chlorination is in progress in order to determine the extent of chlorination as indicated above. Samples may ,be removed from time to time, and the specific gravity of these'bedetermined in order to follow the chlorination process.

If desired, chlorine analyses may beconducted on samples ofthe mterial being chlorinated. After suflicient chlorine has been introduced, we blow-the mixture with air or an inert gas. such as carbon dioxide,

until the hydrogen chlorideand free chlorine, if any, are substantially removed. While it is not essential, thechlorination mixture of the separated relatively pure halogenatedhydrocarbons I may be, given a stabilizing treatment with dilute aqueous solutions of sodium sulflte, sodiumbisulfltefsulfurous acid, potassium permanganate, sodium hypochlorite, or the like.

"As an exampleof the manufacture of 'a relatively pure chlorinated hydrocarbon, we describe here the'man'ufacture of a relatively pure monomelt lower than the hydrocarbons-themselves.

a pure hydrocarbon is employed, a correspondingly pure halide is obtained.

Having selected the hydrocarbon in accordance with the desired final product, we chlorinate the hydrocarbon until approximately that amount of chlorine is absorbed which will produce the monochloro compound when that isthe desired product, or approximately that amount of chlorine chloro, wax which contains approximately 26 carbon atom's'per molecule. We: started with 723.4 parts of a hydrocarbon wax having a melting point of 120 F. The wax was'chlorinated until 72.55 partsdby weight of-chlorine had been absorbed. The chlorinated wax was airblown to remove hydrochloric acid and uncombined residual chlorine, and then pressed at 85 F. The unchlorinated wax was reserved for further 5 chlorination. The liquid portion was then dissolved in acetone, 350 parts.of crude chloro wax' being dissolved in 3,226parts of acetone. The solution was chilled to minus 18 and parts by weight of solid monochloro wax containing 10.3 per cent chlorinewas precipitated. Mono- ,c-hlor wax from this paraiiin wax containstheoretically 10.0.per cent chlorine. Themonochloro wax was normally liquid at i'oomv temperature.

Dichloro waxes and polychloro waxes prepared according to our method are suitable for use in any of the applications described'inthe prior art, where such dichloro.waxes and polychloro waxes are required. Since they contain no unchlorinated wax or lower chlorinated waxes, they are particularly efiicient in these applications and are a distinct improvement over the prior art which used crude chlorination mixtures of approximately the proper chlorine content but which consisted of unchlorinated wax and more highly chlorinated wax.

. While chlorine has been referred to above almost exclusively, it is to be understood that any of the halogens are suitable to make halogen derivatives of the parafiin hydrocarbons according to our method. Thus bromineyiodine, and fluorine may suitably be used to obtain the corresponding bromides, iodides and fluorides. For some purposes to which the halides are to be put, the,bromine compounds are much to be desired over the chlorine compounds, since they are considerably more reactive, Where this is the case, we halogenate with bromine, using a halogen carrier, such as halides of antimony,'ph0sphorus, iron, various metals, and the like, and separate the brominated mixture into its com ponents as described above, in the case of the chlorine compounds. The iodine compounds of the paraffin hydrocarbons may be prepared by direct iodination or by an indirect method. By the indirect method, the above-described separation of mono-, di-, and poly-halogen derivatives may be employed in any step of the process. Thus we may separate a relatively pure monoor dichloro parafim and convert it to the corresponding iodine compound, or we may convert the crude halogenated mixture into a crude iodinated mixture and then separate into the various stages of halogenation. Fluorine may be introduced into paraffin hydrocarbons directly or indirectly by analogous methods. For most purposes, however, we prefer to use the chlorine compounds because of the'cheapness and availability of chlorine above all the other halogens;

In preparing the lubricating oils of our invention, we use these relatively pure monochlor waxes or dichlor waxes and treat them with'metal derivatives of cyclic compounds of the type RXH in which X is an atom of an element selected from the right-hand side of group VI of the periodic table that is, oxygen, sulfur, selenium and tellurium, and R is an organic radical containing at least one cyclic nucleus. We prefer to use the cheap sodium derivatives but other alkali, alkaline earth and heavy metal derivatives of the RXH compounds may be used. These cyclic compounds may be monocyclic, bicyclic or polycyclic, such as phenol, cresols, xylenols, phenylethyl-alcohol, naphthols, hydroxydiphenyls, diand triphenyl carbinols, phenyl cyclohexanol, methyl cyclopentanol, thionaphthols, selenophenol and the like. Even heterocyclic phenols with sodium thiocresolate.

r r A mixture of 139 The reaction whereby our lubricating oils are produced proceeds at satisfactory rates at about 200 C. with most of the ring R'XI-I compounds and most of the halogenated aliphatics, hut temperatures between 100 C. and 300" C. may be used, provided the reaction is not too slow or provided the product is not conveiled to darkcolored products of relatively low viscosity index.

It will be obvious that our relatively pure wax and metal derivative must be substantially dry in order to carry out this rem-Lion. We may use purchased dry metal phcnolates or alcoholates or they may be prepared and treated with the halogen compound in the same reaction vessel. We mix the solid metal derivative with the halogen compound and keep the mixture agitated during the reaction. Usually the mixture is more difiicult to agitate at first than after the reaction has proceeded for a time.

We add water to the reaction mixture and wash out metal halide and excess metal derivative from our synthetic oil. Usually the oil needs only to be dried and this may be accomplished in any suitable manner. For example, we may use a vacuum dehydrator.

We may introduce the group or groups hearing our characterizing elements before or after the condensation reaction to form RXR'. Thus we may condense a metal derivative of an oxygen-substituted phenol such as methyl salicylate with our monochlor wax to form an ether RXR' in which R contains oxygen in the form of the COOCH3 group. Another condensation may be effected between the same metal phenolate and the same number of moles of our dichlor wax. This results in an ether RXR' in which R contains chlorine and R contains oxygen as characterizing elements. Alternatively half the chlorine in our dichlor wax may be removed with sodium ethylate and the product condensed Such a material is of the type RXR' in which X is sulfur, R contains oxygen in the form of .-OC2H5 groups, and R is a hydrocarbon radical.

The following further examples are given as illustrations and not as limitations:

Example 1 parts of o-nitrophenol and 44 parts of sodium hydroxide in 300 parts of toluene was heated. The condensate was separated, discarding the water and returning the toluene to the reaction chamber. When no more water was separable from the distillate, 200 parts of such as S-hydroxy quinoline may be used. It appears to be particularlyadvantageous to have. at least one alkyl group attached to the ring as in p-tert, -butylphenol, octadecylphenol, .penta'cosylphenol, amyl cyclohexanol, and the like. Other substituting groups may be present as in p-nitrophenol, p-hydroxybenzaldehyde, amyl salicylate, p-hydroxyacetophenone, o-hydroxybenzophenone, phenol sulfonic acid, its salts, esters and amides, vanillin, eugenol thymohmesitol, carvacrol, o-chlorophenol, tri-iodophenol, pentachlorophenol, nitrochlorophenols, o-methyl amlnophenol; picramic acid, m-hydroxyazobenzene, thiophenol, selenocresol, resorcinol, hydroquinone monomethyl ether o-chlorobenzyl aioo hol, phenylethyl alcohol, cinnamyl alcohol, and the like.

our relatively pure monochlor wax was added and the toluene removed by distillation. Reaction temperature was held at ISO-180 C. for two hours. Mixture was cooled and water added. 011 was washed several times with water, then with dilute acid and finally steamed to remove any phenolic odor.

Example 2 A mixture of 202 parts of p-hydroxydiphenyl sulfide and 44 parts of sodium hydroxide were melted together and heated at -140 C. for two hours, poured out on a cold surface and pulverized. It was substantially water-free. To this solid was added 200 parts of our relatively pure monochlor waxand the mixture was heated at C. and then at 160 l90 C. for one hour. Mixture was cooled, washed, steamed, and dried.

It is to be understood that any or all of these reactions may be carried out under atmospheric, subatmospheric, or superatmospheric pressure.

Furthermore, various other factors and details" may be changed within wide limits within the spirit of our invention. Our inve marily'in providing an application, of a known I chemical reaction using our relativelypure halo-' gen compounds tov manufacture lubricating oils] ntion lies. pri-f havirm extremely high viscosity indices. While we do not wish to claim the old processe's,,we do wish to claim all novelty inherentin ourprocto proceed so as to remove halogen completely from the aliphaticpart of the ether .but use .a;

halogen-bearing aromatic hydroxy compoundsuch'as p-c'hlorobenzyl alcohol,

For example, we I o-chlorphenol or the like. If desired, a halogenefree condensation product may be halogenated to obtain a halogen bearing lubricatingoil. Any of these-halogenbearing products have superior lubricating properties, particularlyv infilm' strength as compared to the halogen-free lubricating oil. I

Other elements such as sulfur, nitrogen or phosphorus may be present in our lubricating oil molecule. For the former purpose we may use substituted reagents in the condensationsuch as p-nitrophenol, 2-chlor-3 amino-pentacosane, l-mercaptonaphthyl disulfide, hydroxyphenyl diphenyl phosphate, o-hydroxyphenyl diamylphosphine and the like. The finished lubricating product may be so made that it will contain from 0.2 to 20% by weight of one of the halogens, sulfur, nitrogen, phosphorus or combinations of two or more of these. Generally quantities ranging from only 0.2 to 5.0% of these elements are contained in the lubricant. We may add from 0.5 to 20% of other oxygenbearing organic compounds, halogen-containing or halogen-free, such as diphenylene oxide, chlorodiphenylene oxide, chlorinated diphenyls, methyl dichlorostearate, benzyl sulfide, tricresyl phosphate, tri (Z-ethylhexylphenyl) phosphite. benzyl sulfone, sulfurized methyl linoleate, diamyl xanthate, lauryl thiocyanate and the like. Furthermore, we may add various metallic compounds such as chromium oleate, tetra-phenyl lead, aluminum naphthenate, calcium cetyl 3-isopropyl-6-methyl-3, d-endoethylene-A' tetrahydro phthalate, tin octadecyl phthalate, and the like. Examples of some of these blends are:

Solution of per cent naphthalene-chlorwax condensation product in '75 per cent of bright stock 1.5 Sulfurized methyl esters of corn oil acids--- 0.5 Tin phenylstearate 0.2

Example 6 Condensation productof'Example 2 15.0

Condensationproduct of sodium thionaphi It will beseen that wehave accomplished the purpose of our invention; namely, toutilizepetroleum hydrocarbons of low economic value to produce highiviscosity index "lubricating oils o' f great economic value.

sub-'combinationsfare of utility and maybe em ployed without reference sub-combinations; I I I is within the scope of our claim's'. I t' isfurther obvious that various changes maybe made'in details within the scope of therefore, to be understood that our invention is and described.

Having thus described our invention, we claim:

1. A lubricating oil having a viscosity index of over 90, comprising principally an ether of the type YflRXR'Zm, where R is a high molecular weight aliphatic radical having at least 13 carbon atoms, R is an organic radical containing at least one cyclic nucleus, X is an atom of an element selected from the group consisting of oxy-- gen, sulfur, selenium, and tellurium, Y and Z are groups containing an atom of an element selected from the group consisting of oxygen, sulfur, nitrogen, and phosphorus, and m and n are zero-or integers, the sum of which is at least one,

2. A lubricating oil having a viscosity index of over 90, comprising principally a thio-ether of the type YnRSR'zm, where R is a high molecular weight aliphatic radical having at least 13 carbon atoms, R is an organic radical containing at least one cyclic nucleus, Y and Z are groups containing an atom of an element selected from the group consisting of oxygen, sulfur, nitrogen. and phosphorus, and m and n are zero or integers. the sum of which is at least one.

3. A lubricating oil having a viscosity index of over 90, comprising principally a seleno-ether of the type YRRSeRZm, where R is a high molecular weight aliphatic radical having at least 13 carbon atoms, R is an organic radical containing at least one cyclic nucleus, Y and Z are groups containing an atom of an element'selected from the group consisting of oxygen, sulfur, nitrogen and phosphorus, m and n are zero or integers. the sum of which is at least one.

4. A lubricating oil having a viscosity index of over 90, comprising principally a telluro-ether of the type YnRTeRZm, where R is a. high molecular weight aliphatic radical having at least 13 carbon atoms, R is an organic radical containing at least one cyclic nucleus, Y taining an atom of an element selected from the group consisting of oxygen, sulfur, nitrogen and phosphorus, m and n are zero or integers, the sum of which is at least one.

5. A process for the manufacture of lubricating oils having viscosity indices of over 90, comprising the steps of halogenating paraflin hy-,

It will be understood that "certain featuresand to other features and This is contemplated by and I our claims without de- 1 parting fromthe' spirit of our invention: It is,

and Z are groups com I drocarbons whose monochloro derivatives melt lower than the hydrocarbons themselves, separating the mono-, di-, and polyhalogenated hydrocarbons from each other and from unhalogenated hydrocarbons and separately replacing the halogen of each of the said relatively pure halogenated hydrocarbons by means of a metal thiophenolate containing at least one atom of an element selected from the group consisting of oxygen, sulfur, nitrogen, and phosphorus.

6. A process for the production of lubricating oils having viscosity indices of over 90, comprising the steps of halogenating paraflin hydrocarbons whose monochloro derivatives melt lower than the hydrocarbons themselves, separating the mono-, di-, and polyhalogenated hydrocarbons from each other and from unhalogenated hydrocarbons and separately replacing the halogen of each of the said relatively pure halogenated hydrocarbons by means of a metal derivative of an aromatic thioalcohol containing at least one atom of an element selected from the group consisting of oxygen, sulfur, nitrogen, and phosphorus.

7. A process for the production of lubricating oils having viscosity indices of over 90 comprising the steps of halogenating paraflln hydrocarbons whose monochloro derivatives melt lower than the hydrocarbons themselves, separating the mono, di-, and polyhalogenated hydrocarbons weight aliphatic radical having at least 13 carbon atoms, R is an organic radical containing at least one aromatic nucleus, x is an element selected from the group consisting of oxygen, sulfur, selenium, and tellurium, Y and Z are groups containing at least one atom of an element selected from the group consisting of oxygen, sulfur, nitrogen, and phosphorus, and m and n are zero or integers, the sum of which is at least one.

LLOYD L. DAVIS. BERT H. LINCOLN. GORDON D. BYRKIT. 

